Cracking paint/caulk where crown meets ceiling

-- 1 --

Something that has always puzzled me about doing paint-grade crown is...
To glue to ceiling and wall.

I did crown in my living room several years ago and I think I just nailed it up and didnt glue it with caulk and now, where the crown meets the ceiling, it's seperating/cracking. I'm not sure why, so I'll pose the questions..

Do you glue the crown to the ceiling with an adhesive caulk like Poly Seam Seal?

If you do, what caulk do u use?

And 2.... Whos caulk do you use for typical caulking?

I have always found Poly Seam Seal caulk to be the best paintable caulk.

My experience has been this: The best is to nail crown to a ceiling joist when possible and nail lightly to the studs. On walls where you cannot do this I cut angled blocking, nail it to the top plates at the ceiling/wall corner every 16 inches (or you could run a continuous piece) then nail the crown to the blocking. This gives an upward pressure to the crown to stay against the ceiling. If you had the ability, you could nail in blocking before drywall goes up.

As for caulking I have mixed thoughts. I try not to caulk if I am using a stained crown. The color difference hides slight gaps. If I need to caulk, 2 things sometimes happen. If the crown pulls away it can either leave cracked or spidery caulk residue or if the caulk sticks well it can pull the paint off the ceiling which is even worse. So, avoiding it pulling away at all is the best. I do not think caulking ( thinking it will hold it to the ceiling ) even w/ an adhesive caulk is a good long term plan especially in a new house that is likely to shrink and settle right away. This is from experience and more than a few callbacks to renail and/or recaulk mouldings. In large houses it may be hard to eliminate all settling/shrinking callbacks.

One tool that really helped recently was the 3rd hand jack by fastcap. I was able to put nice upward pressure on the crown as I nailed, giving a great fit. And it was like having a free helper.

My experience is mostly with prefinished hardwood mouldings that we scribe to the ceilings. I suppose pine and mdf mouldings would be a little more flexible and easier to work with. hope this helps. Oh as for caulk I have been using phenoseal or a good adhesive caulk when needed.

Thank you for the detailed response! Where can I buy Phenoseal? Is it a latex paintable caulk?

If you cut blocking to nail the crowm to, how much of a gap do you need from the hypotnuse of the angled blocking to the back of the crown? Do you use caulk to clue the blocking and then do you glue the crown to the blocking in obvious addition to the nails?

The crown itself is probably shrinking and the crack at the ceiling is the result. Seasonal expansion and contraction of the house itself can cause cracks in molding/ wall joints.
Phenoseal is a very good adhesive caulk to use; tools easily and cleans up well. It will take any paint you care to use short of auto paint.
For your situation-
"Back in the day" (and I date myself with this) when we still did a lot of hand nailing; I would keep a stock of 12,16 & 20p finish nails in my fastener box. I would nail through the center of the crown at an angle back into the top plates, pulling the crown tight to ceiling and wall at the same time. You may be able to do this if you can get big enough finish nails, then fill, caulk and touch up.

Thanks, mike. Right now I get phenolseal at lowes but they seem to change suppliers often. I do have trouble finding it consistently but I like using their 'transluscent' color which gives some hiding while drying to a milky-white clear for some things.

As for back clearance I leave 1/4-3/8 inch. The perfectionist in me has tried to leave less gap but I have trouble if I have to heavily scribe an area. If I use a 2.5" x 16g air nail or even a 2" x 18g nail it holds well.

My most consistent results have been when I took a 2 x 4 and cut short angled pieces, then nailed them at the ceiling/wall corner above every stud and at each corner and wall outside corner. Or more often if studs are on 24" centers. This gives me a 3.5" wide block to hit. I did not always do this consistently, but I feel like my long term quality has gone up since taking the time to do this. Really most crown looks good when new but I want it to look as good as possible 5 yrs from now also. Hope this helps

If someone had a quicker way I sure would be open to it! This might not be cost effective in a tight budget situation, new house or when using mdf, so I would be open to others views. For instance there is someone in my area advertising crown for like $130 per room, and I wonder how they can do that. Maybe if all furniture was cleared out w/ a simple square room and no paint it would be profitable but... mike

Do you lay the 2x4 flat face down on the 3-1/2" side and cut angles on both long edges, then nail the whole 2x4 up or do you do the same procedure and cut it into like 4" wide blocks and nail them to the studs and ceiling joists?

Then, do you phenoseal the crown to that?

How do you handle crown to ceiling on cabs?

On my own house crown and my imlaws, theres cracking where it meets the ceiling.

My inlaws live on the north shore (very expensive place to live, just north of Chocago) of chicagoland and just had a bathroom re done by a contractor not even 2 months ago and the crown is cracking at the ceiling.

As that leads me to believe one of two things...

1. If its cracking that soon, he must not have used a quality caulk and he certainly didnt put blocking behind.

Is there a good solution to fix the already cracking line, other than tearing it l down and adding blocking?

Do you see any potential for issues if your blocking is a different type of wood or species than what the crown is in regard to expansion and contraction issues? Do you think making 1-1/2" thick blocking out of say raw particle board would be just as good and or effective as a 2x4 used as blocking?

Im right there with you on the perfectionist side of me. I definately have some symptoms of OCD! Lol! I see the cracking and it makes me want to tear it all out and re do it.

I like the other guys solution of using trim screws into the ceiling joists, but what do you do about the areas where you cant do that for crown thats already installed?

I may post a more complete response soon but 1st step is to give the contactor a chance to touch up the crown. I always appreciate a client calling me for a repair instead of them asking around about what to do. Remember I said it is hard to eliminate all cracking. Do you mind me asking are you a DIY er or a contractor? This site is for contactors. You may get more relevant responses from another home repair site. mike

For us personally (GC who does all on many jobs) we caulk nearly everything. Stain or paint. That said, we run everything like stain grade with regards to fit/tight.

On stain grade we run a tiny bead ever so slightly onto the trim and then roll the paint onto that bead. In our experience if the crown is tight and the caulk is dry, we rarely have an issue with cracking. Some of the only times we dont caulk is on interior walls with large trusses above for fear of truss up-lift. Many truss manufacturers today say they have virtually no issues with up-lift but Im a worry wart. So in those circumstances we live with whatever slight gaps there are at the ceiling and caulk to the walls. This would be on trusses 40' and better in cold climates.

The issue of blocking behind the crown is essential if your unwilling to rely on adhesive in some places because in virtually every room, unless the framers were instructed to leave you backing, you will likely have nothing to nail to at the ceilings on walls running parallel with trusses/joist.

We have personally never had a lot of issue with crown cracking but again, we are often times in a turn key situation so we are doing it all and not left chasing/wondering about other subs and what/how they did things.

On most standard crowns I virtually never back it with blocking but we are perhaps 95% stain grade. Often times it seems with paint grade guys will get a bit sloppy relying on caulk to "make it right" but thats of course a mistake for a multitude of reasons. We find in either application, as little caulk as possible the better.

I have on occasion tried the long finish spike (galvanized for grip) or a trim head through the center of the crown into the top plates but its extremely easy to crack the crown, especially the thin commercial stuff, in my opinion.

I simply use a method I saw a long time ago making simple gauge blocks for the spring angle, marking the wall and ceiling, then installing and nailing wherever possible followed by caulk.

For paint grade, and if your really looking for something with high elasticity and massive bridging capabilities, try Quad for your caulk. Youll have to deal with solvent cleanup and tooling (mineral spirits) but you can polish it down like a gasket and it will remain elastic forever. Its my go-to caulk for anything other than painters caulk.

For cabs to plaster your going to have to allow for some movement somewhere because its simply inevitable. The best place for that in my opinion is at the cab/crown joint. So we opt to fasten tightly to the ceiling, caulk, and then lightly nail or pin to the cabs. Your never going to caulk that joint anyway so a little movement there will never be apparent.

Heres molding i just did in my powder room and put phenoseal white does it all caulk on the back side to essentially glue it to the wall and its cracking away in just one day. I caulked it, primed it a few hours later, amd we t to put my paint on and noticed it cracked. Wtf!

We always used to have arguments about which caulk is better for trim install. People often like the look and application of Phenoseal, which is a vinyl based adhesive/sealeant. However, eventually it becomes rock hard and will shrink enough that it breaks the joint. Those are the hairline cracks.

Ideally you want an elastomeric gap filler that expands and contracts with the house movement. The best ones would be polyurethane based ones like PL. Except you can't afford it and the cleanup is a mess.
We typically use a high quality acrylic which will not harden over time. Alex Plus has proven it's self over a couple of decades. Cleanup and application are not as nice as Phenoseal, but it still looks good years later.

If its a single story home or a room with trusses. I find in the winter time the bottom chord of the truss bows upward. (truss lift). I was seen a ceiling lift 1 inch off of 5 pcs oak crown. come summer couldn't tell it had happened.
! solution for truss lift.

2 x 12 blocking on top of walls and screw drywall to blocks not the truss at the edges of walls.

Im back.... 5 months later... Crown is still cracking. I took 3/4" solid poplar and cut triangular blocks, used the last caulk i noted a link for and glued/nailed it to the wall studs and studs and ceiling joists on the two walls.

Why the heck is it stil cracking? This is at my inlaws who have notability told me the humidifier for the second zone (second floor where crown is at) hasnt worked correctly in months). Could the not so moist air do this (no matter what I do)? I used 18 gauge 2" brads.

I'm at a loss for what else to try. Should i run a full 2x4 of pine behind the crown or spent a bit more and mitered solid poplar to nail to? Full piece

WOODWEB is a professional industrial woodworking site. Hobbyist and homeowner woodworking questions are inappropriate.

Messages should be kept reasonably short and on topic, relating to the focus of the forum. Responses should relate to the original question.

A valid email return address must be included with each message.

Advertising is inappropriate. The only exceptions are the Classified Ads Exchange, Machinery Exchange, Lumber Exchange, and Job Opportunities and Services Exchange. When posting listings in these areas, review the posting instructions carefully.

Subject lines may be edited for length and clarity.

"Cross posting" is not permitted. Choose the best forum for your question, and post your question at one forum only.

Messages requesting private responses will be removed - Forums are designed to provide information and assistance for all of our visitors. Private response requests are appropriate at WOODWEB's Exchanges and Job Opportunities and Services.

Messages that accuse businesses or individuals of alleged negative actions or behavior are inappropriate since WOODWEB is unable to verify or substantiate the claims.

Posts with the intent of soliciting answers to surveys are not appropriate. Contact WOODWEB for more information on initiating a survey.

Excessive forum participation by an individual upsets the balance of a healthy forum atmosphere. Individuals who excessively post responses containing marginal content will be considered repeat forum abusers.

Responses that initiate or support inappropriate and off-topic discussion of general politics detract from the professional woodworking focus of WOODWEB, and will be removed.

Participants are encouraged to use their real name when posting. Intentionally using another persons name is prohibited, and posts of this nature will be removed at WOODWEB's discretion.

Carefully review your message before clicking on the "Send Message" button - you will not be able to revise the message once it has been sent.

You will be notified of responses to the message(s) you posted via email. Be sure to enter your email address correctly.

WOODWEB's forums are a highly regarded resource for professional woodworkers. Messages and responses that are crafted in a professional and civil manner strengthen this resource. Messages that do not reflect a professional tone reduce the value of our forums.

Messages are inappropriate when their content: is deemed libelous in nature or is based on rumor, fails to meet basic standards of decorum, contains blatant advertising or inappropriate emphasis on self promotion (return to top).

Libel: Posts which defame an individual or organization, or employ a tone which can be viewed as malicious in nature. Words, pictures, or cartoons which expose a person or organization to public hatred, shame, disgrace, or ridicule, or induce an ill opinion of a person or organization, are libelous.

Improper Decorum: Posts which are profane, inciting, disrespectful or uncivil in tone, or maliciously worded. This also includes the venting of unsubstantiated opinions. Such messages do little to illuminate a given topic, and often have the opposite effect. Constructive criticism is acceptable (return to top).

Advertising: The purpose of WOODWEB Forums is to provide answers, not an advertising venue. Companies participating in a Forum discussion should provide specific answers to posted questions. WOODWEB suggests that businesses include an appropriately crafted signature in order to identify their company. A well meaning post that seems to be on-topic but contains a product reference may do your business more harm than good in the Forum environment. Forum users may perceive your references to specific products as unsolicited advertising (spam) and consciously avoid your web site or services. A well-crafted signature is an appropriate way to advertise your services that will not offend potential customers. Signatures should be limited to 4-6 lines, and may contain information that identifies the type of business you're in, your URL and email address (return to top).

There are often situations when the original message asks for opinions: "What is the best widget for my type of shop?". To a certain extent, the person posting the message is responsible for including specific questions within the message. An open ended question (like the one above) invites responses that may read as sales pitches. WOODWEB suggests that companies responding to such a question provide detailed and substantive replies rather than responses that read as a one-sided product promotion. It has been WOODWEB's experience that substantive responses are held in higher regard by our readers (return to top).

The staff of WOODWEB assume no responsibility for the accuracy, content, or outcome of any posting transmitted at WOODWEB's Message Boards. Participants should undertake the use of machinery, materials and methods discussed at WOODWEB's Message Boards after considerate evaluation, and at their own risk. WOODWEB reserves the right to delete any messages it deems inappropriate. (return to top)

Forum Posting Form Guidelines

Your Name

The name you enter in this field will be the name that appears with your post or response (return to form).

Your Website

Personal or business website links must point to the author's website. Inappropriate links will be removed without notice, and at WOODWEB's sole discretion. WOODWEB reserves the right to delete any messages with links it deems inappropriate. (return to form)

E-Mail Address

Your e-mail address will not be publicly viewable. Forum participants will be able to contact you using a contact link (included with your post) that is substituted for your actual address. You must include a valid email address in this field. (return to form)

Subject

Subject may be edited for length and clarity. Subject lines should provide an indication of the content of your post. (return to form)

Thread Related Link and Image Guidelines

Thread Related Links posted at WOODWEB's Forums and Exchanges should point to locations that provide supporting information for the topic being discussed in the current message thread. The purpose of WOODWEB Forums is to provide answers, not to serve as an advertising venue. A Thread Related Link that directs visitors to an area with inappropriate content will be removed. WOODWEB reserves the right to delete any messages with links or images it deems inappropriate. (return to form)

Thread Related File Uploads

Thread Related Files posted at WOODWEB's Forums and Exchanges should provide supporting information for the topic being discussed in the current message thread. Video Files: acceptable video formats are: .MOV .AVI .WMV .MPEG .MPG .FLV .MP4 (Image Upload Tips) If you encounter any difficulty when uploading video files, E-mail WOODWEB for assistance. The purpose of WOODWEB Forums is to provide answers, not to serve as an advertising venue. A Thread Related File that contains inappropriate content will be removed, and uploaded files that are not directly related to the message thread will be removed. WOODWEB reserves the right to delete any messages with links, files, or images it deems inappropriate. (return to form)

The editors, writers, and staff at WOODWEB try to promote safe practices.
What is safe for one woodworker under certain conditions may not be safe
for others in different circumstances. Readers should undertake the use
of materials and methods discussed at WOODWEB after considerate evaluation,
and at their own risk.